Caster, a construction block set comprising the caster and a method of producing the caster

ABSTRACT

A caster, a construction block set comprising the caster and a method of producing the caster. The caster comprises a housing and a wheeled member rotatably attached to the housing, wherein the housing includes an integrated connecting structure arranged to facilitate a separable connection between the housing and a modular assembly, thereby providing a wheeled function to the modular assembly when the caster is installed.

BACKGROUND OF THE INVENTION

Construction block sets may include basic units of bricks, plates or tiles in different sizes which allow users to build an assembly of different shapes, structures and appearances. In addition, functional components such as wheels may be mounted on the assembled block to provide a wheeled function. For example, two wheels connected by a rotational shaft may be added onto two sides of a built structure, with the rotational shaft passing through the structure therebetween.

SUMMARY OF THE INVENTION

The invention relates to a caster, a construction block set comprising the caster and a method of producing the caster, and particularly, although not exclusively, to a caster which functions as a wheel for a modular toy.

In accordance with a first aspect of the invention, there is provided a caster comprising a housing and a wheeled member rotatably attached to the housing, wherein the housing includes an integrated connecting structure arranged to facilitate a separable connection between the housing and a modular assembly, thereby providing a wheeled function to the modular assembly when the caster is installed.

In an embodiment of the first aspect, the wheeled member comprises a wheel body and a pair of spindles fixed on opposite sides of the wheel body, wherein the wheeled body is rotatably attached to opposite side walls of the housing via the pair of spindles.

In an embodiment of the first aspect, the wheel body comprises a spherical shape, and the housing comprises a substantially rectangular shape.

In an embodiment of the first aspect, the housing includes side walls with a thickness of 1.2 m to 1.5 mm.

In an embodiment of the first aspect, the wheeled body includes a diameter of 11 mm.

In an embodiment of the first aspect, the wheeled body the side walls of the housing are separated by a gap of 1 mm to 2 mm at minimum.

In an embodiment of the first aspect, a portion of the wheel body extends beyond a lowermost edge of the housing, and wherein the wheel body is arranged to contact with a lower surface where the modular assembly is placed thereon.

In an embodiment of the first aspect, the integrated connecting structure includes at least one stud or knob arranged to match with one or more tubes or bar structures on the modular assembly.

In an embodiment of the first aspect, the modular assembly comprises a brick, a plate or a tile defined with the one or more tubes or bar structures.

In an embodiment of the first aspect, the modular assembly defines a body of a toy car built with a plurality of bricks, plate or tile.

In an embodiment of the first aspect, the at least one stud or knob are provided on a top surface of the housing.

In an embodiment of the first aspect, the wheeled member is assembled with the housing via press fitting.

In an embodiment of the first aspect, the housing is made of ABS, and wherein the wheeled member is made of ABS or TRP.

In accordance with a second aspect of the invention, there is provided a method of producing a caster in accordance with the first aspect, comprising the steps of: providing a housing and a wheeled member as separate components; and assembling the caster by connecting the wheeled member to the housing.

In an embodiment of the second aspect, the wheeled member is assembled with the housing via press fitting.

In an embodiment of the second aspect, the housing and/or the wheeled member is made by injection molding.

In accordance with a third aspect of the invention, there is provided a construction block set comprising a plurality of bricks, plate or tile arranged to form a modular assembly when being connected together via integrated connecting structures provided thereon, and one or more casters in accordance with the first aspect.

BRIEF DESCRIPTION OF THE DRAWINGS FOR THE INVENTION

Embodiments of the present invention will now be described, by way of example, with reference to the accompanying drawings in which:

FIG. 1 is a perspective view of a caster in accordance with an embodiment of the invention;

FIG. 2 is an example illustration of the caster of FIG. 1 connectable to a brick or a tile of a modular assembly;

FIGS. 3A, 3B, 3C, 3D, 3E, 3F and 3G are schematic top view, side view, cross-sectional view, front view, bottom view, top perspective view and bottom perspective view of the caster of FIG. 1 and the dimensions of the caster in accordance with an example embodiment of the invention;

FIGS. 4A, 4B, 4C, 4D and 4E are schematic top view, side view, cross-sectional view, front view, and perspective view of the wheeled member of the caster of FIG. 1 and the dimensions of the wheeled member in accordance with an example embodiment of the invention;

FIGS. 5A, 5B, 5C, 5D, 5E, 5F and 5G are schematic top view, side view, cross-sectional view, front view, bottom view, top perspective view and bottom perspective view of the caster of FIG. 1 and the dimensions of the caster in accordance with an example embodiment of the invention;

FIG. 6 is a photographic image showing a top view and a bottom view of the caster (as fabricated) of FIG. 1 ; and

FIGS. 7A, 7B and 7C are photographic images showing different views of a modular toy car installed with the casters of FIG. 1 at the bottom of the toy car.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT OF THE INVENTION

With reference to FIGS. 1 to 7 , there is shown an embodiment of a caster 100 comprising a housing 102 and a wheeled member 104 rotatably attached to the housing 102, wherein the housing 102 includes an integrated connecting structure arranged to facilitate a separable connection between the housing 102 and a modular assembly, thereby providing a wheeled function to the modular assembly when the caster 100 is installed.

In this embodiment, the caster or rotating mechanism 100 comprises a housing 102 which may be considered as a frame or support structure of the caster 100, and a wheeled member 104 such as a sphere rotatably connected to the housing 102 via spindles or an axle, such that when the caster 100 is installed on multiple positions at the bottom of an object, the object is then provided with a wheeled function by allowing the sphere to roll with respect to the housing 102 fixed to the bottom of the object. For example, the object may be a modular toy car built by a plurality of bricks, plates or tiles connected together to form an assembly, and the casters 100 mounted at the bottom of the body of the toy car may then function as wheels of the toy car that facilitate movement of the toy car on a surface. An example of mounting a number of casters to a toy car body will be described in later in this disclosure, with reference to FIGS. 7A to 7C.

In this disclosure, “top” and “bottom” refers to relative positions of the part or portions of the assembly when it is normally placed or deployed on a surface, for example, when a toy car is placed on a ground surface, the wheels are normally in contact with the ground surface such that the wheel at the bottom facilitates movement of the toy car, wherein the roof of the toy car is provided at the top portion.

Referring to FIG. 1 , the housing 102 comprises a substantially rectangular shape, defined by four side walls 102W and a cover having a top surface 1021, which combine to define an internal cavity suitable for accommodating a wheeled member 104 therein. On the top surface 1021, four studs 106 (also known as knobs) are formed thereon, which may function as integrated connecting structure that facilitates a separable connection between the housing 102 and a modular assembly, such as bricks, plates or tiles. In addition, on two opposite side walls 102W of the housing 102, notches 118 and apertures 116 are formed thereon which may receive the spindles of the wheeled member 104 connected the housing 102.

The caster 100 further comprises a wheeled member 104, which has a spherical wheel body 110 and a pair of spindles 112 fixed on opposite sides of the spherical wheel body 110. The wheel body 110 is substantially housed within the internal cavity, i.e. surrounded by the side walls 102W and covered by the cover at the top, however, a portion of the wheel body 110 extends beyond a lowermost edge 102E of the housing 102, such that the wheel body 110 may be in contact with a lower surface where the modular assembly or the toy car is placed thereon.

The exposed portion should be sufficient to allow the wheel body 110 to contact with the ground surface and prevent the housing 102 from getting in touch with the ground surface to prevent the housing 102 and hence the toy car from dragging when it travels on the ground surface. Preferably, the lowermost edge 102E may be set to raise from the lowest point of the wheel body 110 to about ⅔ of the radius of the spherical wheel body 110. For example, for a spherical wheel body 110 with a 5.5 mm radius, about 3.2 mm is exposed above the ground surface and is not covered by the sidewalls of the housing 102 in one preferred embodiment as shown in FIGS. 3B and 3D.

Alternatively, the shape of each of the housing 102 and the wheel body 110 may be different. For example, the wheel body may be alternatively provided in a cylindrical shape, with spindles fixed on the central rotational axis of the cylinder at opposite sides of the cylinder, or the wheel body may include an elliptical cross-section when viewing from the back or the front with spindles fixed on two sides, both variations may function well to roll on the surface as desired when assembled to the housing 102 of the caster 100.

In addition, the shape and dimension of the housing 102 may be different, as long as it is sufficient to house the wheeled member 104 and rotatably fix the spindles 112 on two sides of the wheel body 110. For example, the housing 102 may be provided in cylindrical shape which may house a wheeled member 104 having a spherical wheel body 110, and the housing 102 has a top flat surface 102T that may be used to connect to the matching connecting structures at the bottom of the modular assembly as described above.

In an alternative embodiment, the connection between the housing 102 and the wheel body 110 may be implemented by other possible rotatable connections. For example, instead of allowing the spindles 112 that are fixed to the wheel body 110 to rotate relative to the housing 102, a central axle may be fixed to the housing 102 and the wheel body 110 may be rotatable relative to the central axle to realize the wheeled function.

Referring also to FIG. 2 , the studs or knobs 106, which are integrally formed on the top surface 1021 of the housing 102, may be used to connect the caster 100 to other bricks or tiles in a modular assembly or block, by engaging the protruding studs/knobs 106 into matching connecters at a surface of these blocks/tiles. For example, the connecting structures may be defined by the sidewalls and the tubes or bars at the bottom of each of these bricks or tiles, such that the cylindrical “button-like” knobs or studs 106 may be press fit into the bottom of the bricks or tiles. Preferably, the connections between the caster 100 and the bricks/tiles may be separable, such that the casters 100 may be flexibly mounted, uninstalled and relocated as desired, similar to the separable connections among other bricks or tiles in a same construction block set.

The example bricks 202/204 on the left and the right as shown in FIG. 2 are provided with bars 206 or tubes 208 at the bottom of the bricks and are capable of receiving studs arranged in a 1×3 array and a 2×3 array respectively, therefore may be connected to the caster 100 with the top surface 1021 defining studs arranged in a 2×2 array. As appreciated by a skilled person in the art, the number of studs, and their dimensions, shapes and/or pitch may be different in various design of the connections in different modular systems. Alternatively, or additionally, these studs or knobs may also be provided on other surfaces of the housing 102, which may facilitate attaching the casters 100 to positions other than to the bottom of the modular assembly, while maintaining the exposed wheel body 110 to be at the lowermost bottom position in the complete assembly.

With reference to FIGS. 3A to 5G, the caster 100 has the following preferred dimensions in each of the housing 102 and the wheeled member 104.

As described earlier, the housing 102 has a substantially rectangular shape which, in this example embodiment, has a dimension of 15.8 mm×15.8 mm×9.5 mm (W×L×H), in which the thickness of the side walls 102W and the top cover in a range of around 1.2 to 1.5 mm, which results in an internal cavity 102C of 12.82 mm×12.82 mm×8.1 mm.

Referring specifically to FIGS. 4A to 4E, the wheeled member 104 has a total width of 15.61 mm, which includes the diameter of the spherical wheel body 110 (11 mm) and the length of the spindles 112 at both sides of the wheel body 110. The diameter of the spindles is 2 mm. In addition, a spacer ring 114 of about 0.8 mm thickness and 3 mm diameter may be provided between each of the spindle 112 and the wheel body 110, so as to keep the wheel body 110 in place when it is assembled with the housing 102.

Referring to FIGS. 5A to 5G, an aperture 116 with a diameter of 2.04 mm is provided on each of left- and right-side walls 102W, for holding the spindles 112 of the wheeled member 104 when the wheeled member 104 is assembled with the housing 102, the aperture 116 is slightly larger than the diameter of the spindle 112 to reduce friction being generated when the spindles are spinning. In addition, a taper-shaped notch 118 may be provided to facilitate assembling of the wheeled member 104 to the housing 102, in which the wheel body 110 may be put in place in the internal cavity 102C of the housing 102 by press fitting, with the spindles 112 passing through the notches and reaching the aperture 116. As shown in the Figure, the taper-shaped notch 118 has a wider opening at the lower most edge of the housing 102, which is preferably 2.22 mm wide, and is narrowed to a size slightly smaller than the diameter of the spindle 112, i.e. <2 mm, such that the spindle 112 is secured in the aperture 116 and is prevented from escaping from the aperture 116 via the notch 118 easily.

To ensure smooth rotation of the wheeled member 104 housed within the internal cavity 102C of the housing 102, preferably, the wheel body 110 and the side walls 102W of the housing 102 are separated by a gap of 1 mm to 2 mm at minimum, so as to prevent the housing 102 from hindering the rotational movement of the wheel body 110.

As described earlier in the disclosure, the top surface 102T of the housing 102 is provided with a plurality of knobs or studs 106 which may be used to connect the housing 102 to other bricks or tiles. Preferably, the knobs or studs 106 may include a pitch (i.e. distance from the center point of the knobs) of 8 mm and a diameter of 4.88 mm each, and the height of the studs may be 1.8 mm. In addition, the distance between the center of the outermost studs and the side edge of the housing 102 may be 3.9 mm.

The abovementioned dimensions may be varied in different construction blocks sets or applications, in which each of the studs, the housing 102 and the wheeled member may be scaled to different sizes according to the specifications each of the modular systems. For example, all the sizes of the studs, the housing 102, and the diameter of the wheel body 110 and the spindles of the wheeled member 104 may be enlarged for being used in a construction block set with larger pieces of bricks or tiles.

The caster 100 may be produced by using a method comprising the following steps, including: providing a housing 102 and a wheeled member 104 as separate components; and assembling the caster 100 by connecting the wheeled member 104 to the housing 102.

After producing each of the wheeled member 104 and the housing 102, preferably, the wheeled member 104 may be assembled with the housing 102 via press fitting. In this example, the spindles 112 may be aligned to the notches 118 on opposite side walls 102W, and then the spherical-shaped wheel body 110 may be pressed into the internal cavity 102C defined by the side walls 102W and cover of the housing 102, with the spindles 112 move into the apertures on both sidewalls as described earlier, referring also to the image as shown in FIG. 6 .

Preferably, the housing 102 and/or the wheeled member 104 may be made by injection molding, which allows both components to be made of various choices of materials. For example, the housing 102 may be made of ABS, and the wheeled member 104 may be made of ABS or TPR, in which a single set mold may be used to produce both the housing 102 and the wheeled member 104 if both components are to be made of ABS, or separate set molds may be used for produce each of the housing and the wheeled member 104 if the two components are made of different materials.

Referring also to FIG. 1 , an injection molding gate 108 may be provided at one of the knobs (e.g., the top right one) on the housing 102. The gate may be used to deliver the molten plastic from the nozzles of molding machines.

Alternatively, other plastics or material may be used, in addition, other manufacturing methods including addictive manufacturing or 3D printing may be applied to produce each of these components.

With reference to FIGS. 7A to 7C, there is shown an example modular assembly, which is a toy car 700 built with a plurality of bricks, plate or tile. In this example, the body 702 of the toy car is built with these bricks, with studs/knobs on the top surface 102T and the connecting bars/tubes at the bottom, and therefore the caster 100 may be installed to the toy car by connecting the knobs at the top surface 102T of the housing 102 to the matching connecting structures at the bottom of the bricks of the body of the toy car. For example, four casters 100 may be mounted at the bottom of the toy car 700 so as to facilitate smooth movement of the toy car on a plane surface.

To remove the casters 100 from the toy car 700, the casters 100 may be separated from the body 702 of the toy car simply by pulling away each of the casters 100 from the bottom surface of the body 702 until the connection between the studs/knobs disengage with the connecting structures of the body 702 of the toy car 700, and then the caster 100 may be reinstalled to the toy car at the same or different positions, or used in other modular assembly or construction block as desired.

It is also appreciated that the casters 100 may be used in other toys, apparatus, models, devices, equipment, or any other objects or items and therefore would not be limited to application to toy cars or toys generally. The casters 100 may be used for the construction of other toys or models in the form of other types of vehicles, mechanical models, trains, ships, airplanes, machinery, buildings or it may be adapted for use in other applications in devices, equipment or any other objects or items.

In an alternative embodiment, one or more casters may be mounted to other structure which require a wheeled function, for example, a wooden board may be transformed to a trolley by mounting a number of casters at the bottom of the wooden board defined with connecting structures which matches with the knobs/studs of the caster.

These embodiments may be advantageous in that, each unit of caster includes only two parts which may be easily manufactured by injection molding, and then combined as a single assembly simply by press fitting.

Advantageously, the caster can be easily connected to other bricks or tiles in a separable manner, just like connections among other bricks or tiles in the same construction block set or modular assembly system, therefore it may be easily fixed on different positions of the assembly provided that vacant matching connecting structures are available for connecting the studs of the caster.

For the purposes of this specification, the term caster may be interchanged with the term castor or a rotating mechanism, and the caster, castor or rotating mechanism may include both a rigid caster or a swivel caster and therefore, by definition, the term caster or castor does not need to necessarily be able to swivel or pivot when mounted. As described in some embodiments above, the caster is rigid and therefore does not include any swivel mechanism and would therefore be engaged to provide a rotation means in a straight line for an object which it is engaged with. In some other embodiments, a rotating plate, such as those that include a pair of plates stacked upon each other and may rotate about a central axis, may be engaged to each of the caster and in turn, engage with another object to which the caster is fixed to adapt the caster into a swivel, pivot or turn-able caster.

It will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the invention as shown in the specific embodiments without departing from the spirit or scope of the invention as broadly described. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.

Any reference to prior art contained herein is not to be taken as an admission that the information is common general knowledge, unless otherwise indicated. 

1. A caster comprising a housing and a wheeled member rotatably attached to the housing, wherein the housing includes an integrated connecting structure arranged to facilitate a separable connection between the housing and a modular assembly, thereby providing a wheeled function to the modular assembly when the caster is installed.
 2. A caster in accordance with claim 1, wherein the wheeled member comprises a wheel body and a pair of spindles fixed on opposite sides of the wheel body, wherein the wheeled body is rotatably attached to opposite side walls of the housing via the pair of spindles.
 3. A caster in accordance with claim 2, wherein the wheel body comprises a spherical shape, and the housing comprises a substantially rectangular shape.
 4. A caster in accordance with claim 3, wherein the housing includes side walls with a thickness of 1.2 mm to 1.5 mm.
 5. A caster in accordance with claim 3, wherein the wheeled body includes a diameter of 11 mm.
 6. A caster in accordance with claim 3, wherein the wheeled body the side walk of the housing are separated by a gap of 1 mm to 2 mm at minimum.
 7. A caster in accordance with claim 2, wherein a portion of the wheel body extends beyond a lowermost edge of the housing, and wherein the wheel body is arranged to contact with a lower surface where the modular assembly is placed thereon.
 8. A caster in accordance with claim 7, wherein the integrated connecting structure includes at least one stud or knob arranged to engage with one or more tubes or bar structures on the modular assembly.
 9. A caster in accordance with claim 8, wherein the modular assembly comprises a brick, a plate or a tile defined with the one or more tubes or bar structures.
 10. A caster in accordance with claim 9, wherein the modular assembly defines a body of a toy car built with a plurality of bricks, plate or tile.
 11. A caster in accordance with claim 8, wherein the at least one stud or knob are provided on a top surface 102T of the housing.
 12. A caster in accordance with claim 3, wherein the housing is made of ABS, and wherein the wheeled member is made of ABS or TRP.
 13. A method of producing a caster in accordance with claim 12, comprising the steps of: providing a housing and a wheeled member as separate components; and assembling the caster by connecting the wheeled member to the housing.
 14. A method of producing a caster in accordance with claim 13, wherein the wheeled member is assembled with the housing via press fitting.
 15. A method of producing a caster in accordance with claim 13, wherein the housing and/or the wheeled member is made by injection molding.
 16. A construction block set comprising a plurality of bricks, plate or tile arranged to form a modular assembly when being connected together via integrated connecting structures provided thereon, and one or more casters in accordance with claim
 1. 